Across
- 2. average mass of the naturally occurring isotopes of an element
- 5. no electrical charge; located in the nucleus
- 6. the number of protons does not change in an ____
- 7. number of protons
- 8. have a positive charge; located in the nucleus
Down
- 1. equal to the number of protons plus neutrons
- 3. two atoms with different numbers of neutrons \
- 4. Tiny, very light particles Have a negative electrical charge (-) Move around the outside of the nucleus